Source: Science at the Crossroads: Papers Presented to the International Congress of the History of Science and technology Held in London from June 29th to July 3rd, 1931 by the delegates of the U.S.S.R, Frank Cass and Co., 1931
Online Version: For marxists.org May, 2002
The crisis of present-day capitalist economy has produced a most profound crisis in the whole of capitalist culture; a crisis in individual branches of science, a crisis in epistemology, a crisis in world outlook, a crisis in world feeling. In such historical circumstances the question of the interrelations between theory and practice has also become one of the most acute problems, and, moreover, as a question both of theory and of practice simultaneously. Therefore we have to examine problems from various aspects: (a) as a problem of epistemology, (b) as a problem of sociology, (c) as a problem of history, (d) as a problem of modern culture. Lastly, it is interesting (e) to verify the corresponding theoretical conceptions from the gigantic experience of the revolution, and (f) to give a certain forecast.
I.--The epistemological importance of the problem.
The crisis in modern physics--and equally in the whole of natural science, plus the so-called mental sciences (Geisteswissenschaften)--has raised as an urgent problem, and with renewed violence, the fundamental questions of philosophy: the question of the objective reality of the external world, independent of the subject perceiving it, and the question of its cognisability (or, alternatively, non-cognisability). Nearly all the schools of philosophy, from theologising metaphysics to the Avenarian-Machist philosophy of "pure description" and renovated "pragmatism," with the exception of dialectical materialism (Marxism), start from the thesis, considered irrefutable, that "I" have been "given" only "my" own sensations." This statement, the most brilliant exponent of which was Bishop Berkeley,  is quite unnecessarily exalted into a new gospel of epistemology. When, for example, M. Schlick  on this basis builds up a completely "final" ("durchaus endgultige") turning point in philosophy, it sounds quite naive. Even R. Avenarius  thought it necessary to emphasise all the instability of this initial "axiom." Yet at the present time Berkeley's thesis is strolling up and down all the highways of modern philosophy, and has become rooted in the communis doctorum opinio with the tenacity of a popular prejudice. Nevertheless, it is not only vulnerable, but will not stand the test of serious criticism. It is defective in various respects; to the extent that it contains "I" and "my"; to the extent that it contains the conception of "given"; and lastly to the extent that it speaks "only of sensations."
In point of fact, it is only in the case of the first-created Adam, just manufactured out of clay and for the first time seeing, again with eyes opened for the first time, the landscape of paradise with all its attributes, that such a statement could be made. Any empirical subject always goes beyond the bounds of "pure" sensual "raw material"; his experience, representing the result of the influence of the external world on the knowing subject in the process of his practice, stands on the shoulders of the experience of other people. In his "I" there is always contained "we." In the pores of his sensations there already sit the products of transmitted knowledge (the external expression of this are speech, language and conceptions adequate to words). In his individual experience there are included beforehand society, external nature and history--i.e., social history. Consequently, epistemological Robinson Crusoes are just as much out of place as Robinson Crusoes were in the "atomistic" social science of the eighteenth century.
But the thesis criticised is defective not only from the standpoint of "I," "my," "only sensations." It is defective also from the standpoint of "given." Examining the work of A. Wagner, Marx wrote: "The doctrinaire professor represents the relations of man and nature from the very outset not as practical relations--i.e., those founded on action, but as theoretical... but people never begin under any circumstances with 'standing in theoretical relationship with objects outside the world.' Like other animals, they begin by eating, drinking, etc.--i.e., they do not 'stand' in any relationship, but function actively, with the help of their actions take possession of certain objects of the outside world, and in this way satisfy their requirements. (Consequently they begin with production.)
Thus the thesis criticised is incorrect also because it expresses a calmly passive, contemplative point of view, and not an active, functioning point of view, that of human practice, which also corresponds to objective reality. Thus, the far-famed "irrefutable" epistemological "axiom" must fall to the ground. For it is in categorical contradiction to objective reality. And it is in just as categorical contradiction to the whole of human practice; (1) it is individualistic and leads directly to solipsism; (2) it is anti-historical; (3) it is quietist. Therefore it must be rejected with all decisiveness.
Lest there should be any misunderstanding: we entirely adopt the standpoint that sensuality, sensual experience, etc., having as their source the material world existing outside our consciousness, constitute the point of departure and beginning of cognition. It was just from this that began the philosophical rebellion of Feuerbach against the yoke of the idealistic abstractions and panlogism of Hegel. Of course, individual sensations are a fact. But historically there is no absolutely unmixed individual sensation, beyond the influence of external nature, beyond the influence of other people, beyond the elements of mediated knowledge, beyond historical development, beyond the individual as the product of society--and society in active struggle against nature. And in the "axiom" under consideration, what is important is its logical "purity." If the latter disappears, the whole "axiom" disappears. For this reason the arguments which we put forward are actual arguments.
From the above it can already be seen what a vast role, the problem of theory and practice plays from the standpoint of epistemology.
We pass now to the consideration of this theme.
First of all, it should be noted that both theory and practice are the activity of social man. If we examine theory not as petrified "systems," and practice not as finished products--i.e., not as "dead" labour petrified in things, but in action, we shall have before us two forms of labour activity, the bifurcation of labour into intellectual and physical labour, "mental and material," theoretical cognition and practical action. Theory is accumulated and condensed practice. To the extent that it generalises the practice of material labour, and is qualitatively a particular and specific continuation of material labour, it is itself qualitatively a special, theoretical practice, to the extent that it is active (cf. e.g., the experiment)--practice fashioned by thought. On the other hand, practical activity utilises theory, and to this extent practice itself is theoretical. In actual fact we have in every class society divided labour and, consequently, a contradiction between intellectual and physical labour--i.e.. a contradiction between theory and practice. But, like every division of labour, here too it is a living unity of opposites. Action passes into cognition. Cognition passes into action. Practice drives forward cognition. Cognition fertilises practice. Both theory and practice are steps in the joint process of "the reproduction of social life." It is extremely characteristic that from of old the question has been asked: "How is cognition possible?" But the question is not asked: "How is action possible?" There is "epistemology." But no learned men have yet thought of inventing some special "praxeology." Yet one passes into the other, and Bacon himself suite justifiably spoke of the coincidence of knowledge and power, and of the interdependence of the laws of nature and norms of practice.  In this way practice breaks into the theory of cognition, theory includes practice, and real epistemology, i.e., epistemology which bases itself upon the unity (not the identity!) of theory and practice, includes the practical criterion, which becomes the criterion of the truthfulness of cognition.
The relative social disruption of theory and practice is a basis for a break between the theory of cognition and practical action, or for the construction of a super-experimental theory as a skilled free supplement to the usual and earthly forms of human knowledge.  Hegel has the unity of theory and practice in a particularly idealistic form (unity of the theoretical and practical idea as cognition), unity which overcomes the onesidedness (Einseitigkeit) of theory and practice, taken separately, unity "precisely in the theory of cognition." In Marx we find the materialistic (and simultaneously dialectical) teaching of the unity of theory and practice, of the primacy of practice and of the practical criterion of truth in the theory of cognition. In this way Marx save a striking philosophical synthesis, in face of which the laboured efforts of modern pragmatism, with its theological and idealistic contortions, its super-artificial and laborious constructions of fictionalism, etc., seem but childish babble.
The interaction between theory and practice, their unity, develops on the basis of the primacy of practice. (1) Historically: the sciences "grow" out of practice, the "production of ideas" differentiates out of the "production of things"; (2) sociologically: "social being determines social consciousness," the practice of material labour is the constant "force motrice" of the whole of social development; (3) epistemologically: the practice of influence on the outside world is the primary "given quality." From this follow extremely important consequences. In the exceptionally gifted "theses" of Marx on Feuerbach, we read:
"Die Frage, ob dem menschlischen Denken gegenstandliche Wahrheit zukomme - ist keine Frage der Theorie, sondern eine praktische Frage. In der Praxis muss der Mensch die Wahrheit, d.h. Wirklichkeit und Macht, Diesseitigkeit seines Denkens beweisen. Der Streit über die Wirklichkeit oder Nichtwirklichkeit des Denkens, das von der Praxis isoliert ist-ist eine rein scholastiche Frage," (2nd Thesis.)
"Die Philosophen haben die Welt nur verschieden interpretiert; es kommst darauf an, sie zu verandern." (11th Thesis.)
The problem of the external world is here put as the problem of its transformation: the problem of the cognition of the external world as an integral part of the problem of transformation: the problem of theory as a practical problem.
Practically--and, consequently, epistemologically--the external world is "given" as the object of active influence on the part of social, historically developing man. The external world has its history. The relations growing up between subject and object are historical. The forms of these relations are historical. Practice itself and theory, the forms of active influence and the forms of cognition, the "modes of production" and the "modes of conception," are historical. The question of the existence of the external world is categorically superfluous, since the reply is already evident, since the external world is "given," just as practice itself is "given." Just for this reason in practical life there are no seekers after solipsism, there are no agnostics, no subjective idealists. Consequently epistemology, including praxiology, epistemology which is praxiology, must have its point of departure in the reality of the external world: not as a fiction, not as an illusion, not as a hypothesis, but as a basic fact. And just for this reason Boltzmann "declared with every justification that the premise about the unreality of the external world is "die grösste Narrheit, die je ein Menschengehirn ausgebrutet hat": it is in contradiction to all the practice of humanity. Whereas E. Mach, in his "Analysis of Sensations," considers that from the scientific (and not the practical) standpoint the question of the reality of the world (whether it exists in reality, or whether it is an illusion, a dream) to be impermissible, since "even the most incongruous dream is a fact no worse than any other." This "theory of cognition" acquired from Vaihinger a demonstrative character, as he erected fiction into a principle and "system" of cognition. This peculiar somnambulistic epistemology was foreseen in his day by Calderon:
Que es la vida? Un frenesi:
Que es la vida? Una illusion,
Una sombre, una ficcion,
Y el mayor bien es pequeño.
Que toda la vida es sueno,
Y los suenos sueno son.
Practice is an active break-through into reality, egress beyond the limits of the subject, penetration into the object, the "humanising" of nature, its alteration. Practice is the refutation of agnosticism, the process of transforming "things in themselves" into "things for us," the best proof of the adequacy of thought, and of its truth--understood historically, as a process. For, if the objective world is changed through practice and according to practice, which includes theory, this means, that practice verifies the truth of theory; and this means that we know to a certain extent (and come to know more and more) objective reality, its qualities, its attributes, its regularities.
Therefore the fact of technology, as Engels already remarked in "Anti-Dühring," confutes Kantian agnosticism--that "paltry doctrine," in the words of Hegel. If K. Pearson in a "Grammar of Science" modernises the well-known cave of Plato, replacing it by a telephone exchange, and the pale shades of the Platonic ideas by telephone signals, he thereby demonstrates his own conception of the passively-contemplative character of cognition. The real subject--i.e., social and historical man--is not in the least like either Karl Pearson's telephonist or the observer of the Platonic shades. He likewise does not in the least resemble that stenographer, inventing "convenient signs in shorthand, into whom the philosophising mathematicians and physicists desire to transform him (B. Russell, Wittgenstein, Frank, Schlick, and others). For he is actively transforming the world. He has changed the face of the whole of the earth. Living and working in the biosphere, social man has radically remoulded the surface of the planet. The physical landscape is ever more becoming the seat of some branch of industry or agriculture, an artificial material medium has filled space, gigantic successes of technique and natural science confront us, the radius of cognition, with the progress of exact apparatus of measurement and new methods of research, has grown extremely wide: we already weigh planets, study their chemical composition, photograph invisible rays, etc. We foretell objective changes in the world, and we change the world. But this is unthinkable without real knowledge. Pure symbolism, stenography, a system of signs, of fictions, cannot serve as an instrument of objective changes, carried out by the subject.
Cognition, considered historically, is the more and more adequate reflection of objective reality. The fundamental criterion of the correctness of cognition is therefore the criterion of its adequateness, its degree of correspondence to objective reality. The instrumental criterion of truth is not in contradiction to this criterion, but coincides with it, if it is only a question of an instrument for the practice of social man, transforming the objective world (Marx's "revolutionare Praxis," Engels' "umwalzende Praxis"), and not of the individual "practice" of any philistine in a beershop. Therefore the "instrumental criterion" of pragmatism (Bergson, close to pragmaticism; W. James and others) must be rejected with all decisiveness. James includes as practice, prayer, the "experience" of religious ecstasy, etc.; doubting the existence of the material world, he does not doubt at all the existence of God, like, by the way, many other adherents of so-called "scientific thought" (A. S. Eddington, R. A. Millikan, etc.). The criterion of economy of thought can in no way serve as a criterion, since the economy itself can only be established post factum: while taken in isolation, as a bare principle of cognition in itself, it means the a priori liquidation of the complexity of thought--i.e., its deliberate incorrectness. In this way "economy" is transformed into its very opposite. "Man's thinking is only 'economic' when it correctly reflects objective reality, and the criterion of this correctness is practice, experiment, industry."
We see, consequently, that modern capitalist theories of cognition either do not deal with the question of practice altogether (Kantianism: cf. H. Cohen: "Logik der reinen Erkenntnis," 1902, p. 12."Wir fangen mit dem Denken an. Das Denken darf keinen Ursprung haben ausserhalb seiner selbst"), or treat of practice in the Pickwickian sense, tearing it away from the material world or from "the highest" forms of cognition (pragmatism, conventionalism, fictionalism, etc.). The only true position is held by dialectical materialism, which rejects all species of idealism and agnosticism, and overcomes the narrowness of mechanical materialism (its ahistorism, its anti-dialectical character, its failure to understand problems of quality, its contemplative "objectivism," etc.).
II.--Theory and Practice from the Sociological Standpoint. Historical Forms of Society and the Connection of Theory and Practice.
Dialectical materialism, as a method of cognition applied to social development, has created the theory of historical materialism. The usual conception of Marxism is that of a variety of the mechanical, natural-scientific materialism typical of the teachings of the French encyclopaedists of the xviii. century or Buchner-Moleschott. This is fundamentally wrong. For Marxism is built up entirely on the idea of historical development, foreign to the hypertrophied rationalism of the encyclopaedists. The question of theory in general must be put as follows from what is said above--from the standpoint of social theory--i.e., the standpoint of sociology and history.
At the present time all scientists more or less acquainted with the facts, and all research workers, recognise that genetically theory grew up out of practice, and that any branch of science has, in the long run, its practical roots. From the standpoint of social development, science or theory is the continuation of practice, but--to adapt the well-known remark of Clausewitz--"by other means." The function of science, in the sum total of the process of reproduction of social life, is the function of orientation in the external world and in society, the function of extending and deepening practice, increasing its effectiveness, the function of a peculiar struggle with nature, with the elemental progress of social development, with the classes hostile to the given socio-historical order. The idea of the self-sufficient character of science ("science for science's sake") is naive: it confuses the subjective passions of the professional scientist, working in a system of profound division of labour, in conditions of a disjointed society, in which individual social functions are crystallised in a diversity of types, psychologies, passions (as Schiller says: "Science is a goddess, not a milch cow"), with the objective social role of this kind of activity, as an activity of vast practical importance. The fetishising of science, as of other phenomena of social life, and the deification of the corresponding categories is a perverted ideological reflex of a society in which the division of labour has destroyed the visible connection between social function, separating them out in the consciousness of their agents as absolute and sovereign values. Yet any--even the most abstract--branch of science has a suite definite vital importance in the course of historical development. Naturally, it is not a question of the direct practical importance of any individual principle--e.g., in the sphere of the theory of numbers, or the doctrine of quantities, or the theory of conditioned reflexes. It is a question of systems as a whole, of appropriate activity, of chains of scientific truths, representing in the long run the theoretical expression of the "struggle with nature" and the social struggle. Active relationship with the external world, which at the purely animal stage of human development presupposes the natural organs of man, as a variety of hominis sapientis, is replaced by relationship through the medium and with the help of the "continuation of those organs," i.e., with the help of the "productive organs of social man" (Marx), the implements of labour, and systems of social technique. At first this system is really the "continuation" of the organs of the human body. Later it becomes complicated, and acquires its own principles of movement (e.g., the circular motions of modern machinery). But at the same time there develops historically also orientation in the external world, again with the help of artificial instruments of cognition, instruments of "spiritual" labour, extending a gigantic number of times the sphere of action of the natural organs of the body and the instruments of orientation. Micro-balances, the water-level, seismographs, the telephone, the telescope, the microscope, the ultra-microscope, the chronoscope, the Michelson grating, electrical thermometers, bolometers, the photo-electrical element of Elster and Geitel, galvanoscopes and galvanometers, electrometers, the apparatus of Ehrenhaft and Millikan, etc., etc.--all these immeasurably widen our natural sensual capacities, open new worlds, render possible the victorious advance of technique. It is a piece of historic irony, at the expense of the greatly multiplied agnostics who completely fail to understand the value of transmitted knowledge, and reduce the whole process of cognition to the production of tautology, that precisely the electrical nature of matter is the "last word" of science: since it is just the "electrical feeling" which we lack. "Yet the whole world of electricity was discovered to us none the less by means of the application of artificial organs of sensation." Thus there have proved to be historically variable both the "organs of sensation" and the so-called "picture of the world," verified by the gigantic practice of modern humanity as a whole, a "picture of the world" much more adequate to reality than all its predecessors, and therefore so fruitful for practice.
And so man is historically given as social man in contradistinction to the enlightened Robinsons of Rousseau, "founding society and history like a chess club, and with the help of a "contract." This social man, i.e., human society, in order to live, must produce. Am Anfang war die Tat (in contrast to the Christian Logos: "In the beginning was the Word"). Production is the real starting point of social development. In the process of production there takes place a "metabolism" (Marx) between society and nature. In this process, active on the part of historical and social man, a material process, people are in definite relationship one with another and with the means of labour. These relations are historical, their totality constitutes the economic structure of society. It is also a historic variable (in contradistinction to the theories of "society generally," "eternal society," "ideal society," etc.). The economic structure of society (the "mode of production") includes, above all, the relationship between classes. On this basis there grows up the "superstructure": political organisations and State power, moral norms, scientific theories, art, religion, philosophy, etc. The "mode of production" determines also the "mode of conception ": theoretical activity is a "step" in the reproduction of social life; its material is furnished by experience, the breadth of which depends on the degree of power over the forces of nature, which is determined, in the long run, by the development of productive forces, the productivity of social-labour; the level of technical development. Stimuli proceed from the tasks set by practice; the forming principles, the "mode of conception" in the literal sense, reflect the "mode of production," the socio-class structure of society and its complex requirements (the idea of rank, authority, the hierarchy and the personal God in feudal society; the idea of the impersonal force of fate, of the elemental process, of the impersonal God in capitalist commodity-society," etc.). The prevailing conceptions are those of the ruling class, which is the bearer of the given mode of production.
But, just as development in natural history changes the forms of biological species, the historical development of society, with the movement of productive forces at its foundation, changes the socio-historic forms of labour, "social structures," "modes of production," together with which there changes the whole ideological superstructure, up to and including the "highest" forms of theoretical cognition and reflective illusions. The movement of productive forces, the contradiction between them and the historic forms of social labour are, consequently, the cause of the change in these forms, realised through class struggle (to the extent that we are speaking of class societies) and the blowing up of the out-of-date social structure, transformed from "a form of development" to "fetters on development." In this way the practice of material labour is the basic motive force of the entire process as a whole, the practice of the class struggle is the critical-revolutionary practice of social transformation ("criticism weapons" which takes the place of the "weapon of criticism"), the practice of scientific cognition is the practice of material labour continued in particular forms (natural science), of administration and the class struggle (the social sciences). The "class subjectivism" of the forms of cognition in no way excludes the objective "significance" of cognition: in a certain measure cognition of the external world and social laws is possessed by every class, but the specific methods of conception, in their historical progress, variously condition the process of the development of the adequateness of cognition, and the advance of history may lead to such a "method of conception" as will become a fetter upon cognition itself. This occurs on the eve of the destruction of the given mode of production and its class promoters.
It is from this historico-materialist angle that we should also approach the exceptionally complicated question of the interrelations between the theoretical ("pure") and applied sciences. Here there is a considerable number of various solutions: (a) to take as a criterion the difference between causal theoretical series ("Natürgesetz," law) and teleological, normative series (rule, system of rules, prescriptions); (b) to take as a criterion distinction according to objects--the "pure" sciences study the natural surroundings given to man: the applied sciences the artificial surroundings (machines, transport technique, apparatus, raw materials, etc.); (c) to take as criterion time (the "pure" sciences work with a long period in view, forestalling developments, the applied serve "the needs of the moment"); (d) to take as criterion, lastly, the degree of generality ("abstractness") of the particular science.
On this subject it is necessary to remark (a) on the first criterion: "sciences" teleologically set forth at bottom are not sciences, but arts (Künste). However, any system of norms (we have not here in mind ethics and the like) depends upon a system of objective laws, which are either covertly understood or directly set forth as such. On the other hand, the sciences in the particular sense of the word ("pure sciences") are not "pure," since the selection of an object is determined by aims which are practical in the long run--and this, in its turn, can and must be considered from the standpoint of the causal regularity of social development.
(b) On the second criterion: engineering, for example, may be set forth as a "pure" study--i.e.. theoretically, without norms, without constructive rules; however, usually in its enunciation we also have a teleological and normative element. The same has to be said, e.g., of the resistance of materials, the science of staple commodities, and so forth. This is not an accident, for here the object itself ("the artificial surroundings") is material practice.
(c) On the third criterion: a vividly practical task may also be "protracted" (e.g., the problem of aeronautics, as it stood for a number of centuries, or--at the present time--the transmission of energy from a distance), a task which always has its "purely theoretical" equivalent as well.
(d) On the fourth criterion: a very concrete science may also be "purely theoretical," since knowledge has broken up into a number of rivulets, and has become extremely specialised. It would hardly come into anyone's head, for example, to classify the Japhetic theory of language among the applied sciences, although it also, of course, is bound up with a number of the most important practical tasks. (Here we should also note the relativity of the conceptions of concrete and abstract.)
And so, apparently, all the definitions are defective. The most accurate definition is the division according to the characteristic of causal and teleological series. However, here too we see obvious defects from the standpoint of actual relationship. But all these defects of logical definition reveal the objective dialectics of reality: contradictions arise here because there is an objective contradiction between theory and practice, and at the same time their unity; there is their difference, as opposite poles of human activity, and at the same time their interpretation; there is their separate existence as functions, as branches of divided social labour, and at the same time their unitary existence, as steps in the joint "production of social life." Under the cover of the difficulty of the exact demarcation of the applied and theoretical sciences beats the dialectics of the relationship between theory and practice, the passing of one into the other: which does not fit--and cannot fit--into the framework of school-logic and academical-pedantic definitions. In reality we have a whole chain of various theoretical sciences, linked up by internal connections ("the classification of sciences, of which each analyses a separate form of motion or a number of interconnected forms of motion which pass into one another, is also a classification or hierarchy of these very forms of motion according to the order inherent in them: and just in this lies its significance.") These sciences are born out of practice, which first sets itself "technical" tasks: the latter require, in their turn, the solution of "theoretical" problems, problems of the first, second, etc., order, a special (relative) logic of motion being thereby created. Practice in this way grows into theory: the sought-for rule of action is transformed into the search for the law of objective relationship: there arise innumerable knots and interlacings of problems with their solutions: these, in their turn, sometimes fertilise a number of hierarchically lower branches of science, and through technology penetrate into technique--consequently, into the direct practice of material labour, transforming the world. Here law becomes transformed into a rule of action, the percipient decision is verified by that action, orientation in the surroundings becomes the alteration of those surroundings, the intellect is immersed in the will, theory once again reverts to the form of practice. But this metamorphosis has as its final result by no means a simple repetition of the previous cycle of practice, since practice becomes practice on a more powerful and qualitatively altered basis.
The problem of the "pure" and "applied" sciences, reflecting and expressing the problem of theory and practice, is not however a purely logical problem. It is itself a problem of history, and a problem of transforming historical practice. The acuteness of the problem in the innermost recesses of the capitalist order, and even the seeing of the problem itself, is the theoretical expression of the real separation, fixed in terms of profession and class, and rupture between theory and practice--a rupture, naturally, relative and not absolute. This rupture, consequently, is a historical phenomenon: it is bound up with a definite historico-economic formation, with a definite historically transitory "mode of production," with the bifurcation of labour into intellectual and physical labour, with the polarisation of classes. It may therefore be said with every justification that socio-economic formations ("modes of production," "economic structures") differ from one another also in the particular character of the relationship between theory and practice. And in fact, in the theocratic state of Ancient Egypt there were elements of a natural centralised planned economy; knowledge (theory) was most closely connected with practice, since it was expediently directed towards practice. But this connection was of a special type. Knowledge was inaccessible to the mass of workers: their practice for them was blind, and knowledge was surrounded with an aureole of dread mystery. In this sense there was a vast rupture between theory and practice. If we take for comparison the epoch of industrial capitalism, the epoch of the flourishing of "economic man," of boundless individualism, of "laissez faire," we see a different picture. On a social scale no one puts forward in an organised fashion either problems of cognition or problems of application of acquired knowledge. The division of labour creates a group of scientists and ideologues, bound up with the ruling class, which in its turn is broken to pieces by competition. The connection between theory and practice is to a considerable extent built up "privately." But the bifurcation of intellectual and physical labour does not disappear: it receives a different expression--a certain degree of "democratisation of knowledge," necessary from the standpoint of technique: the formation of a large stratum of technical and other intelligentsia: the specialisation of science: the creation of high theoretical generalisations, completely remote from the consciousness of the mass of practical workers (wage-workers). This is another type of connection. Its inevitable consequence is the abstract and impersonal fetishism of science (science for science's sake), the disappearance of the social self-consciousness of science, etc. Modern capitalism reproduces this anarchy on the new and more powerful basis of trustified industrial complexes and the corresponding scientific organizations. But it cannot either discover a scientific synthesis, or attain the self-knowledge of science, or achieve its organization, or its fusion with practice. These problems, which are poignantly felt, lead already beyond the boundaries of capitalism.
III.--Theory and Practice of the U.S.S.R. and the Empirical Test of Historical Materialism.
It follows from all the foregoing that the question of theory and practice is simultaneously both a theoretical and a practical question: that both theory and practice, and likewise the forms of combination of theory and practice, are bound up with a definite historical order of society, its development, its "motion." Therefore it is beyond all doubt that a particularly stormy course of social life (a revolution) and a new social order (Socialism im Werden) are of exceptional interest from the standpoint of the problem we are considering.
All knowledge is tested in practice, by experience. The same has to be said of the systematised knowledge, of theory, theoretical tendency, "doctrine." It is relevant here to record, first of all, that Marxism, weighed in the balance of history, has been verified therein in the most varied directions. Marxism foretold the war; Marxism foretold the period of revolutions and the whole character of the epoch we are going through; Marxism foretold the dictatorship of the proletariat and the rise of a Socialist order; even earlier had been brilliantly justified the theory of the concentration and centralisation of capital, etc. The Revolution has proved the great destroyer of fetishes, laying bare the fundamental links and interdependences of society in their real significance. The State appeared to bourgeois science now as a distinct organism (even up to the point of determining its sex), now as a fantasy, now as an expression of the "Absolute Spirit," now as the universal organisation of the popular will, etc. The Revolution has destroyed one State and built up another: it has practically invaded this sphere of reality, and has ascertained the component parts of the State, and its functions, and its personnel, and its "material appendages," and its class significance, and its significance from the standpoint of economics. The Revolution has completely confirmed the theoretical teaching of Marx on the State. The same has happened to the norms of law, with "law" itself: juridical fetishism has burst into atoms. Morality, which found its "theoretical justification" in the categorical imperative of Kant, and which reached its highest stage of deification, disclosed itself to be a system of relative historical norms, with a quite earthly, quite social, and suite historical origin. Religion, which is revered as the highest product of human thought, proved to be a cast taken from a society of lords and slaves, a construction on the model of a dualist society, on the model of a hierarchical ladder of domination and exploitation. For this very reason it began rapidly to die out.
But the revolution in reflective categories, which was the inevitable result of the material revolution, has not yet concluded. We are patently viewing its first phase. Here it is necessary to dwell on some problems in this connection, related to the question of theory and practice.
The capitalist economic order is a system of unorganised elementally developing, and as a whole irrational economic life ("anarchy of production," competition, crises, etc.). The Socialist economic order is a system of organised, planned, and anti-exploiter economy, in which little by little there disappears the division between town and country, intellectual and physical labour. Hence follow vast consequences. First of all, it is necessary to note the changes in the character of social regularity. The regularity of capitalism is an elemental regularity, coming into existence irrespective of (and sometimes against) the will of man (typical examples are the regularity of the industrial cycle, of crisis, etc.). This regularity shows itself in the shape of a compulsory law, "like the law of gravity when a house falls on your head."
In relation to the actions of individual persons this regularity is irrational, even though every one of them should act according to all the rules of rational calculation. This irrational current of life is the consequence of the anarchic character of the capitalist structure. The regularity in organised Socialist society is of a different type. It loses (if we are speaking of a process, it begins to lose) its elemental character: the future lies ahead as a plan, an aim: causal connection is realised through social teleology: regularity shows itself not post factum, not unforeseen, incomprehensible, blind: it shows itself as "recognised necessity" ("freedom is recognised necessity"), realised through action organised on a social scale. Consequently, here is present a different type of regularity, a different relationship between the individual and society, a different relationship between causal and teleological series. In capitalist society the theoretical foreknowledge of the general course of events does not provide the instrument for taking direct control of that course (and there is no subject to set himself such a task: society itself is subjectless, blind, unorganised). In Socialist society the theoretical foreknowledge of the necessity can at once become a norm of action on the scale of the whole of society--i.e., on the scale of "the whole." Thereby is afforded the possibility of the fusion of theory and practice, their gigantic social synthesis, historically more and more realised in the measure of the elimination of the rupture between intellectual and physical labour.
In the economic life of capitalism the elementary social necessity of definite proportions between the branches of production is achieved by means of an elemental fluctuation of prices, in which the law of value expresses itself as the elemental regulator of socio-productive life. In the economic life of Socialism the distribution of resources (means of production and labour power) takes place as a constructive task of a plan. But the plan does not fall from the sky: it is itself the expression of "recognised necessity." Consequently, here (a) the tasks of cognition expand to a colossal degree; (b) this cognition must embrace a huge quantity of problems, and express itself in the work of all branches of science; (c) this cognition must become synthetic, for a plan is a synthesis, and a scientifically elaborated plan can rely only on a synthesis; (d) this cognition is directly bound up with practice: it relies on practice, it serves it, it passes into it, for the plan is active: it is at one and the same time a product of scientific thought, laying bare causal regularities, and a system of purposes, an instrument of action, the direct regulator of practice and its component part. But the plan of Socialist construction is not only a plan of economy: the process of the rationalisation of life, beginning with the suppression of irrationality in the economic sphere, wins away from it one position after another: the principle of planning invades the sphere of "mental production," the sphere of science, the sphere of theory. Thus there arises here a new and much more complex problem: the problem of the rationalisation not only of the material-economic basis of society, but also of the relations between the sphere of material labour and "spiritual labour," and of relations within the latter--the most striking expression of this is the question of the planning of science.
In the ideological life of capitalism a certain social necessity of definite proportions (much less definite than in economic life!) between the various branches of ideological labour is regulated to an extremely small extent by the State (the only sphere which is completely regulated is the production and diffusion of religious ideas through the organisation of the State Church.) The regularities of development are here also elemental. Those basic principles which the theory of historical materialism puts forward cannot serve as a standard of action for the ruling class, on the social scale of that action, for the same reason that a capitalist "plan" is unrealisable: a plan is in contradiction to the very structure of capitalism, the prime dominants of its structure and its development. Here, too, the building of Socialism puts the whole problem in a new way. The elemental regularity of interdependences between economy and ideology, between collective economic practice and the multifarious branches of theoretical labour, yield place to a considerable degree to the principle of planning. At the same time, all the basic proportions of the theory of historical materialism are confirmed: one can feel with one's hands, as it were, how the requirements of the rapid and intensive growth of the U.S.S.R. imperiously dictate the solution of a number of technical problems, how the solution of these problems, in its turn, dictates the posing of the greatest theoretical problems, including the general problems of physics and chemistry. One can feel with one's hands how the development of Socialist agriculture pushes forward the development of genetics, biology generally, and so on. It can be observed how the exceptionally insistent need for the study of the natural wealth of the Union broadens the field of geological research, pushes forward geology, geochemistry, etc. And all the poverty of the idea that the "utility" of science means its degradation, the narrowing of its scope, etc., becomes crystal clear and apparent. Great practice requires great theory. The building of science in the U.S.S.R. is proceeding as the conscious construction of the scientific "superstructures": the plan of scientific works is determined in the first instance by the technical and economic plan, the perspectives of technical and economic development. But this means that thereby we are arriving not only at a synthesis of science, but at a social synthesis of science and practice. The relative disconnection between theory and practice characteristic of capitalism is being eliminated. The fetishism of science is being abolished. Science is reaching the summit of its social self-cognition.
But the Socialist unification of theory and practice is their most radical unification. For, gradually destroying the division between intellectual and physical labour, extending the so-called "higher education" to the whole mass of workers, Socialism fuses theory and practice in the heads of millions. Therefore the synthesis of theory and practice signifies here a suite exceptional increase in the effectiveness of scientific work and of the effectiveness of Socialist economy as a whole. The unification of theory and practice, of science and labour, is the entry of the masses into the arena of cultural creative work, and the transformation of the proletariat from an object of culture into its subject, organiser and creator. This revolution in the very foundations of cultural existence is accompanied necessarily by a revolution in the methods of science: synthesis presupposes the unity of scientific method: and this method is dialectical materialism, objectively representing the highest achievement of human thought. Correspondingly is being also built up the organisation of scientific work: together with concentrated planned economy there is growing the organisation of scientific institutions, which is being transformed into a vast association of workers.
In this way is arising a new society, growing rapidly, rapidly overtaking its capitalist antagonists, more and more unfolding the hidden possibilities of its internal structure. From the standpoint of world history the whole of humanity, the whole orbis terrarum, has fallen apart into two worlds, two economic and cultural-historic systems. A great world-historic antithesis has arisen: there is taking place before our very eyes the polarisation of economic systems, the polarisation of classes, the polarisation of the methods of combining theory and practice, the polarisation of the "modes of conception," the polarisation of cultures. The crisis of bourgeois consciousness goes deep, and traces out marked furrows: on the whole front of science and philosophy we have gigantic dislocations which have been excellently formulated (from the standpoint of their basic orientation) by O. Spann: the main thing is a war of destruction against materialism. This is the great task of culture. in the opinion of the warlike professor, who protests against knowledge without God and knowledge without virtue (Wissen ohne Gott und Wissen ohne Tugend). In economic ideology, under the influence of the crisis of the capitalist system, there has begun the direct preaching of a return "to the pick and the hoe," to pre-machine methods of production. In the sphere of "spiritual culture" the return to religion, the substitution of intuition, "inward feeling," "contemplation of the whole," for rational cognition. The turn from individualist forms of consciousness is patent. It is universal--the idea of "the whole," "wholeness" ("das Ganze," "Ganzheit") in philosophy; in biology (Driesch and the Vitalists), in physics, in psychology (Gestaltpsychologie), in economic geography (territorial complexes), in zoology and botany (the doctrine of heterogeneous "societies" of plants and animals), in political economy (the collapse of the school of "marginal utility," "social" theories, the "universalism" of Spann), and so on, and so forth. But this turn to the "whole" takes place on the basis of the absolute breaking-away of the whole from its parts, on the basis of idealistic understanding of the "whole," on the basis of a sharp turn to religion, on the basis of the methods of super-sensual "cognition." It is not surprising, therefore, that from any scientific hypothesis quasi-philosophic (essentially religious) conclusions are being drawn, and on the extreme and most consistent wing there is openly being advanced the watchword of a new medievalism.
In complete opposition to this comprehensible development, young Socialism is arising--its economic principle the maximum of technical economic power, planfulness, development of all human capacities and requirements its cultural-historical approach determined by the Marxist outlook: against religious metaphysics advancing dialectical materialism: against enfeebled intuitive contemplation, cognitive and practical activism: against flight into non-existent metempirical heavens, the sociological self-cognition of all ideologies: against the ideology of pessimism, despair, "fate," fatum, the revolutionary optimism which overturns the whole world: against the complete disruption of theory and practice, their greatest synthesis: against the crystallisation of an "elite," the uniting of the millions. It is not only a new economic system which has been born. A new culture has been born. A new science has been born. A new style of life has been born. This is the greatest antithesis in human history, which both theoretically and practically will be overcome by the forces of the proletariat--the last class aspirins to power, in order in the long run to put an end to all power whatsoever.
 Cf. Ernest Mach: "Analyse der Empfindungen," and his "Erkenntnis und Irrtum; K. Pearson: "The Grammar of Science, Lond. 1900. H. Bergson: 'L'evolution creatrice," Paris, F. Alcan, 1907. W. James: "Pragmatism," N. York, 1908, and his "The Varieties of Religious Experience," Lond. 1909. H. Vaihinger: "Die Philosophie des Als Ob," Berlin, 1911. H. Poincare: "La Science et l'Hypothese," Paris, E. Flammarion, 1908. In the same circle of ideas there moves the "logistics" of B. Russell. The latest literature on this subject includes the work of Ph. Frank, M. Schlick, R. Carnap, et al. Even the almost materialist Study takes his stand on the principle quoted: cf. his "Die realistische Weltansicht und die Lehre vom Raume," I. Teil: Das Problem der Aussenwelt. 2. ungearbeitete Aufl, Vieweg & Sohn, 1923.
 George Berkeley: "Treatise concerning the Principles of Human Knowledge," vol, i. of Works, ed. Frazer, Oxf., 1871.
 3 Morifz Srhlick: "Die Wende der Philosophie" in "Erkenntnis," vol. i., No. 1. ''Ich bin nämlich uberzeugt, dass wir sachlich berechtigt sind, detl unfruchtbaren Streit der System als beendigt (N.B.) anzuzehen" (p. 5).
 R. Avenarius: "Kritik der reinen Erfahrung," v. I., Leipzig, 1888, pp. vii. and viii.
 K. Marx: "On the book of Adolph Wagner." First published in Marx and Engels Archives, vol. v., pp. 387-388, Moscow, 1930. Marx's italics.
 "Theoretical capacity begins with the presently existing, given, external and transforms it into its conception. Practical capacity, on the contrary, begins with internal definition. The latter is called decision, intention, task. It then transforms the internal into the real and external--i.e., gives it present existence. This transition from internal definition to externality is called activity." "Activity generally is the union of the internal and the external. The internal definition with which it begins, as a purely internal phenomenon, must be removed in its form and become purely external.... On the contrary, activity is also the removal of the external, as it is given directly...The form of the external is changed..". (G. V. F. Hegel: "Introduction to Philosophy," sections 8 and 9.)
 Francis Bacon: "Philosophical Works," ed. J. M. Robertson, London, 1905. "Human knowledge and human power meet in one; for when the cause is not known the effect cannot be produced. Nature to be commanded must be obeyed; and that which in contemplation is as the cause is in operation as the rule" (p. 259.) Franc. Baconis de Verulomio: "Novum Organum Scientiarum." Apud Adrianum Wijngaerum et Franciscum Moiardum, 1645, p. 31. "Scientia et Potentia Humana in idem coincidunt, quia ignoratio causae destituit effectum. Natura enim non nisi parendo vincitur; et quod in Contemplatione instar causae est, id in Operatione instar Regulae est."
 Cf. Marx and Engels: "Feuerbach (Idealistic and Materialist Standpoint)." Marx and Engels Archives, vol. i., p. 221: "Division of labour becomes a real division of labour only when a division of material and spiritual labour begins. From that moment consciousness may in reality imagine that it is something other than the consciousness of existing practice. From the moment that consciousness begins really to imagine something, without imagining something real, from that time onwards it finds itself in a position to emancipate itself from the world and proceed to the formation of 'pure theory,' theology, philosophy, morality, etc."
 "Die Idee als Erkennen, welches in der gedoppelten Gestalt der theoretischen und der praktischen Idee erscheint." (Hegel: "Wissenschaft der Logik," 391 (vi., sec. 215).
 Lenin: Abstract of 'The Science of Logic," Lenin Review, vol. ix., 6. 270.
 Boltzmann: "Populare Schriften," 905.
 E. Mach: "Analyse der Empfindungen."
 R. Vaihinger: "Die Philosophie des Als Oh. System der theoretischen, praktischen und religiösen Fiktionen der Menscheit auf Grund eines idealistischen Positivismus," Berlin, 1911, p. 91. "Das die Materie eine solche Fiktion sei, ist heutzutage eine allgemeine Ueberzeugung der denkenden Kopfe."
 Calderon: "La Vida es Sueno. Las Comedias del celebre poeta español Don Pedro Calderon de la Barca. Zuickavia, Libreria de los hermanos Schumann, 1819.
 F. Engels: Herrn Eugen Duhrings Umwalzung der Wissenschaft."
 "That we do not know realities, and that it has been granted us to know only accidental and passing--i.e., paltry phenomena--that is the paltry doctrine, which has made and is making the loudest noise, and which now predominates in philosophy Hegel: "Encyclopaedia of Philosophic Sciences," Part I., Speech of Oct. 22, 1818.)
 See Y. Vernadsky, Member of Academy: The Biosphere. Leningrad, 1926. (Russian.)
 Characteristic of the modern physicists and mathematicians is the following opinion of Ph. Frank: "Wir sehen: bei keiner Art von solchen Problemen handelt es sich darum, eine 'Uebereinstimmung zwischen gedanken und Objekt,' wie die Schulphilosophie sagt, hervorzubringen, sondern immer nur um die Erfindung eines Verfahrens, das geignet ist, mit Hilfe eines geschickt gewahlten Zeichensystems Ordnung in unsere Erlebnisse zu bringen und dadurch uns ihre Beherrschung zu erleichtern." (Ph. Frank: "Was bedeuten die gegenwartigen physikalischen Theorien fur die allgemeine Erkenntnislehre?" in "Erkenntnis," vol. i., pp. 2-4; pp. 134-135).
 "God is real, since he produces real effects" (517). "I believe the pragmatic way of taking religion to be the deeper way.... What the more characteristically divine facts are, apart from the actual inflow of energy in the faith-state and the prayer-state, I know not ... But the overbelief on which I am ready to make my personal venture is that they exist" (519). William James: "The Varieties of Religious Experience," London, 1909. Cf. also "Pragmatism," p. 76. Study (loc. cit. 65, footnote) rightly observes: "Er (Vaihinger, N.B.), verurteilt den Pragmatismus meretrix theologorum. Ich hatte den Pragmatismus 'die Leib--und Magenphilosophie des banalen Nutzlichkeitsmenschen genannt'."
 Lenin: "Materialism and Empiriocriticism," Works, Eng. ed, vol, xiii.
 It is characteristic that, in spite of this, the numerous "refutations" of Marxism systematically begin with the premise of the mechanical character of dialectical materialism and its sociological side (the theory of historical materialism). Cf. N. N. Alexeyev: "The Social and Natural Sciences in the Historical Interrelation of their Methods. Part I. The Mechanical Theory of Society. Historical Materialism." Moscow, 1912. Other attempts at a deeper criticism are founded on a poor acquaintance with the subject, though their name is legion.
 Cf. on mathematics among the Babylonians, Egyptians, Greeks, Romans, Chinese, Indians, etc. M. Kantor: "Vorlesungen über die Geschichte der Mathematik." Leipzig. Trubner, 1903, vol, i., 3rd ed. Cf. also F. J. Moore: "History of Chemistry." Otto Wiener: "Physics and the Development of Culture." R. Eisler: "Geschichte der Wissenschaften." A. Bordeaux: "Histoire des sciences physiques, chimiques, et geologiques an xix. siecle," Paris et Liege, 1920. "It is necessary to study the successive development of individual branches of natural science. First astronomy--already from year to year absolutely necessary for pastoral and agricultural peoples. Astronomy can develop only with the help of mathematics. Consequently, it became necessary to study the latter, too. Further, at a certain stage of development and in certain countries (the raising of the water level for irrigation purposes in Egypt) and particularly together with the origin of towns, large buildings, and the development of handicrafts, there developed mechanics also. Soon it also became necessary for shipping and the art of war.... Thus from the very beginning the origin and development of Sciences are conditioned by production." (F. Engels: "Dialectics of Nature. Dialectics and Natural Science." Marx and Engels Archives, II., p. 69.)
 Cf. Marx: "Capital," Eng. ed., vol, i., p. 158: "Thus Nature becomes one of the organs of his activity, one that he annexes to his own bodily organs, adding stature to himself in spite of the Bible." Cf. also Ernst Kapp: "Grundlinien einer Philosophie der Technik." Braunschweig, 1877, pp. 42 et seq.
 "....Vielmehr glauben wir, dass nur die Beobachtung uns Kenntnis vermittelt von den Tatsachen, die die Welt bilden, während alles Denken nichts ist als tautologisches Umformen." (Hans Hahn: "Die Bedeutung der wissenschaftlichen Weltauffassung, insbesondere für Mathematik und Physik" in "Erkenntnis," I., Nos. 2-4, p. 97, 1930. The group of empiriocritics fail to understand that the product of perceptive activity is qualitatively different from sensual "raw material," just as the completed locomotive is qualitatively different from its metallic parts, even though 'made' out of them.
 O. Wiener, Op. cit., p. 41.
 This is not a secret for some modern physicists either. "The physical conditions of existence are more fundamental than the aesthetic, moral, or intellectual. A child must be fed before it can be taught. A certain standard of living above that of animals is a preliminary condition for the development of any of the special qualities of human beings." (Frederic Soddy: "Science and Life," London, J. Murray, 1920, p. 3.)
The fashionable German philosopher and author of "Christian-prophetic" "Socialism," Max Scheler, while carrying on a desperate struggle against Marxism, borrows from the latter a number of basic principles, producing as a consequence a perfectly intolerable cacophony of motifs. To illustrate the influence of Marxism on this Catholic philosopher, we quote the following passage from his large work, "Die Wissensformen und die Gesellschaft" (Leipzig, mcmxxvi), pp. 204-205: "So ist es nicht unrichtig, dass selbst sehr formale Arten des Denkens und der Wertnehmung klassenmassig verschieden geartet sind--freilich nur in Gesetzen der grossen Zahl der Fille, da ja jeder die Bindung seiner Klassenlage prinzipiell überwinden kann. Zu solchen klassenmissig bestimmten formalen Denkarten rechne ich beispielweige folgende:-
1. Wert-prospektivismus des Zeitbewussteins-Unterklasse; Wertretrospektivismus-Oberklasse.
2. Werdensbetrachtung-Unterklasse: Seinsbetrachtung-Oberklasse.
3. Mechanische Weltbetrachtung-Unterklasse; teleologische Weltbetrachtung-Oberklasse.
4. Realismus (Welt vorwiegend als 'Widerstand')-Unterklasse: Idealismus-Oberklasse (Welt vorwiegend als 'Ideenreich').
5. Materialismus-Unterklasse; Spiritualismus-Oberklasse.
6. Induktion, Empirismus-Unterklasse; Aprioriwissen, Rationalismus-Oberklasse.
7. Pragmatismus-Unterklasse; Intellektualismus-Oberklasse.
8. Optimistische Zukunftsansicht und pessimistische Retrospektion-Unterklasse. Pessimistische Zukunftsaussicht und optimistische Retrospektion, 'die gute alte Zeit'-Oberklasse.
9. Widerspruche suchende Denkart oder 'dialektische' Denkart-Unterklasse; identitatssuchende Denkart-Oberklasse.
10. Milieu-theoretisches Denken-Unterklasse; nativistisches Denken-Oberklasse."
This original table is extremely schematic and unhistorical, but it contains individual elements of truth. However, this truth does not prevent Scheler from standing pat on the side of the "Oberklasse" and launching into the wilds of appropriate religious metaphysics.
 E. Husserl: "Logical Researches." Cf. M. Lomonosov: "On the Value of Chemistry," Works (St. Petersburg, 1&10), iii., p. 1.
 Paul Niggli: Reins und angewandte Naturwissenschaft. "Die Naturwissenschaften." 19. Jahrffang, Heft I.
 Cf. W. Ostwald: "Der energetische Imperitiv," I. Reihe, Leipzig 1912, pp. 46, 53.
 The attempts, recently still fashionable, of the school of H. Rickert to dig an impassable abyss between the social and natural sciences logically rely upon the naive conception that in the natural sciences, as opposed to the social, there is no "relation to values." This "relation to values" exists in the natural sciences as well, so far as selection of an object is concerned. However, teleology must be driven out of science, as a system of theoretical principles discovering objective regularities, and this applies equally, to the social and the natural sciences. The raison-d'etre of the Rickertian view for the bourgeoisie, however, is that its social science is rapidly declining to scientific non-existence, changing more and more into the simple apology of the capitalist system, which for the Rickerts undoubtedly has a most outstanding "value." As for the other distinction of "principle" made by Rickert (the historical character of the social sciences and the non-historical character of the natural), it relies upon an extreme narrowness of outlook, which takes note of the historical evolution of some social phenomena, but does not see the history of nature. At the present time a new school is arising in place of Rickert-Dilthey--M, Weber, O. Spann, W. Sombart--which proclaims the impossibility of the perception of external nature ("the essence of things") and the full possibility of the perception of the "sense" of social phenomena, Sombart moreover maintaining that the natural sciences have practical value, while the social sciences cannot have any practical application. Truly modern bourgeois science is beginning to walk on its head! Cf. Sombart: Die drei Nationalökonomien v. Geschichte und System der Lehre von der Wirtschaft. Duncker und Humblot, 1930.
 F. Engels: "Dialectics of Nature," pp. 31-33. See also Hegel: "Phenomenology of the Spirit" (St. Petersburg; 1913, p. 112): "Symptoms must not only bear an essential relationship to cognition, but must also be essential definitions of things, so that the artificial system must be in conformity with the system of nature itself, and express only that system."
 A number of other examples might be quoted. Moore, in his "History of Chemistry," already quoted, writes of the Greek philosophers: "They lacked direct acquaintance with chemical transmutations. Owing to their social position they were deprived of direct contact with those who might have communicated practical information to them, while the general spirit of the age forced them to despise experiment, equally with physical work. Only pure thought was considered worthy of a philosopher" (p. 2). "The slow progress of science in antiquity is explained by the dissociation of theory from practice. There existed no contact between those who worked and those who thought" (pp. 9, 10). Cf. also Hermann Diels: "Wissenschaft und Technik bei den Hellenen" in "Antike Technik." (Trubner, Leipzig & Berlin, 1920) pp. 21 et seq. Cf. with this observation Marx on Aristotle in "Capital," vol. I.
 "K. Marx: "Capital," vol. i. Cf. also Engels: "Ludwig Feuerbach,".
 For this see: "Proceedings of the 1st Conference on Planning of Scientific Research Work," Moscow, 1931.
 Otto Neurath: "Wege der wissenschaftlichen Auffassung" ("Erkenntnis" vol. i., No. 2-4, p. 124): "In grosstem Stil planmassig gedankliche Gemeinschaftsarbeit ist als Allemeinerscheinung wohl nur moglich in einer planmassig durchorganisierten Gesellschaft, die mit Hilfe irdisch begrundeter Mittel, straff und bewusst die Lebensordnung in Hinblick auf irdisches Glück gestaltet, Soziale Wandlungen sind Prager geistiger Wandlungen." The same author pays a tribute to the materialist conception of history (p. 121), recognising the fact of the true prognoses drawn up by the Marxists. Quite otherwise has been the philosophic evolution of W. Sombart, who in his last book writes that Marxism owes its "monstrous" power "ausschusslich den in Mystik auslaufenden geschichts-philosophischen Konstruktionen dieser Heilslehre" (Werner Sombart: "Die drei Nationalokonomien," p. 32). This charge of mysticism levelled against Marxism is just as stupid as the previously mentioned "essence" and "sense" of the latest "sociology of sense." And bourgeois science is patently beginning to wander in its accusations against the theory of the revolutionary proletariat?
 Othmar Spann: "Die Krisis in der Volkswirtschaftlehre," p. 10--::... so finden wir...., dass ein ... auf Vernichtung hinzielender Kampf gegen...sagen wir zuletzt Materialismus jeden Schlages, gefuhrt wurde. Selt der Aufklarung gibt es keine lebenswichtigere Angelegenheit der Kultur."
 Cf. E. Morselli: [greek characters] in "Rivista di filosofia," vol. xxi., No. 2, "en ritorno a un nuovo Medio evo che in forme varie agita oggi il pensiero della 'elite' europea" (p. 134). Cf. also Berdiaeff: "Un nouveau Moyen Age." Paris, 1927.